Employee Benefits (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($)
Retirement Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Employer Contribution	$ 3.0
Defined Benefit Plan, Expected Contributions in Current Fiscal Year	10.0
Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Employer Contribution	0.1
Defined Benefit Plan, Expected Contributions in Current Fiscal Year	$ 1.5